Jan. 27, 2012
Courtesy of the University of Veterinary Medicine, Vienna
and World
Science staff

Male house mice pro­duce me­lo­di­ous songs to at­tract mates, not un­like
many birds, ac­cord­ing to new re­search.

The dit­ties are too high-pitched for hu­man hear­ing, but sci­en­tists at Vi­en­na's Un­ivers­ity of Vet­er­i­nary Med­i­cine an­a­lyzed them and found they con­vey in­forma­t­ion about ident­ity and kin­ship. The find­ings are pub­lished in the jour­nal
Phys­i­ol­o­gy & Be­hav­ior and in the Jour­nal of Ethol­o­gy.

The house mouse, spe­cies Mus
mus­cu­lus. Male house mice pro­­duce me­lo­di­ous songs to at­­tract mates, not un­­like many birds, ac­­cord­ing to new re­search.
(Im­age cour­te­sy Maine Dept. of Ag­ri­cul­ture)

“It seems as though house mice might pro­vide a new mod­el or­gan­ism for the study of song in an­i­mals,” said Dus­tin Penn of the uni­vers­ity, one of the co-authors of the work. “Who would have thought
that?”

Sci­en­tists knew house mice make sounds dur­ing court­ship, but as­sumed they were just squeaks, ac­cord­ing to the group. In real­ity, they said, they are com­plex and show char­ac­ter­is­tics of song: dur­ing slowed-down play­backs, a si­m­i­lar­ity to bird song be­comes strik­ing.

The re­search­ers aimed to learn what type of in­forma­t­ion the tiny
croon­ers’ songs con­vey for fe­ma­les' dis­cern­ing ears. Their in­i­tial stud­ies, the first to study song in wild mice, con­firmed that males emit songs when they en­coun­ter a fe­ma­les' scent and that fe­males are at­tracted to the songs. The sci­en­tists al­so found that fe­males can tell apart their broth­ers from un­re­lat­ed males by their songs – even though they had pre­vi­ously nev­er heard their broth­ers sing.

The in­ves­ti­ga­tors recorded and an­a­lysed the court­ship calls of wild-caught male house mice us­ing dig­it­al au­di­o soft­ware to ex­am­ine char­ac­ter­is­tics such as dura­t­ion and pitch. They found the songs con­tain “sig­na­tures” that dif­fer for each in­di­vid­ual, and that the songs of sib­lings are very si­m­i­lar to one an­oth­er com­pared to the songs of un­re­lat­ed ma­les.

Among some birds, the males with the most com­plex songs seem to be most suc­cess­ful at at­tracting fe­ma­les, Penn and col­leagues said, so fur­ther stud­ies might in­ves­t­i­gate wheth­er the same is true in mice. The wild house mice's songs dif­fer sig­nif­i­cantly from those of lab mice, which are gen­er­ally in­bred, the group added: wild mice pro­duce more syl­la­bles with­in high­er pitch ranges than lab mice.

Male house mice produce melodious songs to attract mates, not unlike birds, according to new research.
The ditties are too high-pitched for human hearing, but scientists at Vienna's University of Veterinary Medicine analyzed them and found they convey information about identity and kinship. The findings are published in the journal Physiology & Behavior and in the Journal of Ethology.
“It seems as though house mice might provide a new model organism for the study of song in animals,“ said Dustin Penn of the university, one of the co-authors of the work. “Who would have thought that?“
Scientists knew house mice make these sounds during courtship, but assumed they were just squeaks, according to the group. In reality, they said, the vocalizations are complex and show characteristics of song: during slowed-down playbacks, a similarity to bird song becomes striking.
The researchers aimed to learn what type of information males' songs convey for females' discerning ears. Their initial studies, the first to study song in wild mice, confirmed that males emit songs when they encounter a females' scent and that females are attracted to the songs. The scientists also found that females can tell apart their brothers from unrelated males by their songs – even though they had previously never heard their brothers sing.
The investigators recorded and analysed the courtship calls of wild-caught male house mice using digital audio software to examine characteristics such as duration and pitch. They found the songs contain “signatures“ or “fingerprints“ that differ for each individual, and that the songs of siblings are very similar to one another compared to the songs of unrelated males.
Among some birds, the males with the most complex songs seem to be most successful at attracting females, Penn and colleagues said, so further studies might investigate whether the same is true in mice. The wild house mice's songs differ significantly from those of lab mice, which are generally inbred, the group added: wild mice produce more syllables within higher pitch ranges than lab mice.